So this afternoon I popped the tank onto the bench and removed the sender to get a better look inside and I was amazed at how clean and rust free it was. There is 'dirt' residue on the sidewalls but generally very good.
I was going to seal it to prevent ethanol induced corrosion (the car doesn't get used much). My dilemma now is the in tank filter getting coated in the sealing product, I could use compressed air to blow it clear after application but not sure that would be sufficient.
Anyone else sealed their tank and what did you do with the filter?

Alan